Goodwill and Intangible Assets Intangibles (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 111,445	$ 111,445
Finite-Lived Intangible Assets, Accumulated Amortization	(58,304)	(55,237)
Intangible Assets, Net (Excluding Goodwill)	53,141	56,208
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	14,621	14,621
Finite-Lived Intangible Assets, Accumulated Amortization	(7,349)	(6,973)
Intangible Assets, Net (Excluding Goodwill)	$ 7,272	$ 7,648
Trademarks and Trade Names [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Trademarks and Trade Names [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Technical Library
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Finite-Lived Intangible Assets, Gross	$ 400	$ 400
Finite-Lived Intangible Assets, Accumulated Amortization	(206)	(201)
Intangible Assets, Net (Excluding Goodwill)	194	199
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	91,426	91,426
Finite-Lived Intangible Assets, Accumulated Amortization	(45,751)	(43,065)
Intangible Assets, Net (Excluding Goodwill)	$ 45,675	$ 48,361
Customer Relationships [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 years	6 years
Customer Relationships [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years	15 years
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Finite-Lived Intangible Assets, Gross	$ 40	$ 40
Finite-Lived Intangible Assets, Accumulated Amortization	(40)	(40)
Intangible Assets, Net (Excluding Goodwill)	$ 0	$ 0
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year	1 year
Finite-Lived Intangible Assets, Gross	$ 4,958	$ 4,958
Finite-Lived Intangible Assets, Accumulated Amortization	(4,958)	(4,958)
Intangible Assets, Net (Excluding Goodwill)	$ 0	$ 0